HGS, FDA AGREE ON TRIAL PROTOCOL FOR LUPUS TREATMENT

Human Genome Sciences (HGS) announced it has received a special protocol assessment (SPA) from the FDA, agreeing on the company's Phase III clinical development program for LymphoStat-B (belimumab) in patients with active systemic lupus erythematosus (SLE).

The design of the LymphoStat-B Phase III development program includes a primary efficacy endpoint that emerged directly from the previously reported results of a Phase II clinical trial. The endpoint is a combined patient response rate that includes elements of the SELENA SLEDAI and BILAG disease activity indices, as well as the Physician's Global Assessment index. These measures are well-known to clinical investigators with experience in SLE. The Phase II results show that LymphoStat-B, as measured by this combined response rate, significantly reduced disease activity in serologically active patients, the population in which the drug will be studied in Phase III.

Under the terms of the SPA, and as proposed by HGS, the Phase III development program for LymphoStat-B will include two double-blind, placebo-controlled, multicenter superiority trials, BLISS-52 and BLISS-76, which will evaluate the efficacy and safety of LymphoStat-B plus standard of care, versus placebo plus standard of care, in the treatment of patients with active SLE. The primary efficacy endpoint of both studies is the patient response rate at week 52, as defined by: a reduction from baseline in the SELENA SLEDAI score of at least four points; no worsening in Physician's Global Assessment (with worsening defined as an increase of more than 0.30 points from baseline); no new BILAG A organ domain score and no more than 1 new BILAG B organ domain score from baseline.

LymphoStat-B is a human monoclonal antibody that specifically recognizes and inhibits the biological activity of B-lymphocyte stimulator, or BLyS. BLyS is a naturally occurring protein discovered by HGS that is required for the development of B-lymphocyte cells into mature plasma B cells. Plasma B cells produce antibodies, the body's first line of defense against infection.